Adjustable stop



April 1959, M. FRESARD ET AL 2,883,868

ADJUSTABLE STOP Filed Feb. 5, 1957 Fig.5

%4RCEL FEESHED fem/r00 m/w/m 22/ United States Patent f ADJUSTABLE STOP Marcel Fresard and Rolando Gianinazzi, Geneva, Switzerland, assignors to Mefina S.A., Fribourg, Switzerland, a corporation of Switzerland Application February 5, 1957, Serial No. 638,340

Claims priority, application Switzerland February 20, 1956 4 Claims. (Cl. 74-96) The present invention has for its subject a control device for a machine, comprising an arm carrying an operating member capable of being moved into a plurality of positions of which at least one is secured by a lock-. ing device, said position determining a given adjustment of the machine.

Control devices of this character are used in very diverse fields of technology and particularly in connection with sewing machines.

In fact, the mechanism for adjusting the length of point and of reversal of the direction of movement of the feeder of a sewing machine is, in general, controlled by a device of this character. However, when using control parts of moulded or pressed material in sewing machines, adjustments of the mechanism of the sewing machine require to be carried out, in view of the relatively large tolerances which occur in the manufacture of these parts in moulded or pressed material. These parts, in some sewing machines, form cams for the control of movements of the machine.

The present invention has for itsobject to enable an adjustment of the character to be avoided during the mounting of each part of moulded material.

The control device according to the present invention is characterized in that its operating member is mounted rotatably at the end of the arm and is secured to a part which is eccentric relatively to its axis of rotation, said eccentric part producting a movement of the arm relatively to the axis of rotation of the operating 1 member during an angular movement of the latter, whereby a fine adjustment of the machine is rendered possible.

One form of construction of the device according to the invention is shown diagrammatically and by way of example in the accompanying drawings, wherein:

Fig. l is a view in side elevation of said control device.

Fig. 2 shows a detail of Fig. 1.

Fig. 3 is a view to a larger scale and in section of the control device.

Fig. 4 shows the operating member visible on the outside of the machine.

Fig. 5 is a section on the line V-V of Fig. 3.

The control device shown in the accompanying drawing is precisely the device used in some sewing machines in which a cam of pressed or moulded material is used for controlling automatic variations of the movements of the feeder.

This device comprises a hub 1, hinged to a spindle 2 which, for example, may at the same time, be a shaft for controlling the movements of the needle of the sewing machine. Said hub 1 has an arm 3, of which the end 4 serves as a stop for a member 5 which may form, for example, the part on which pivots the feeler finger of the control cam. It is therefore precisely said member 5 which should be capable of adjustment to some extent during the mounting of a new cam in the sewing machine.

The hub 1 has a second or socket arm 6 extended by a rod 7 mounted in such a manner as to be capable 2,883,868 -Patented Apr. 28, 1959 of turning in the arm 6. The outer end of said rod 7 carries an operating member 8 formed, in this particular case, by a milled knob, for example, of pressed material.

The hub 1 is free on the spindle 2 and is provided with a radial socket arm 6 which rotatably receives an extension rod 7. This rod, turnable in the socket arm 6, is connected to the handle or knob 8 thereby to be actuated-through a limited are as will be presently seen. The arm 6 passes through a slot 9 in a scale segment 10 which may be a part of the casing of the machine.

The rod 7 is provided generally in the zone of the slot 9 with an eccentric portion 19. A slide 11 is fixed on the rod 7 for limited axial movement relative thereto by the pegs 14 and 17 and the circular bore 20 of the slide surrounds said eccentric portion 19.

A shoe 12 is fitted on the rod 7 for sliding movement over the outer face of the segment 10.

The slide 11 is medially provided with diametrically opposed locking projections 13 disposed at the inner face of the segment 10 and adapted selectively to cooperate with a related notch 18 for holding the rod in a given position in relation to'the scale on the segment 10.

The compression spring 15 housed in the recess 16 of the knob or handle 8 tends to press the slide 11 and shoe 12 toward each other so that the locking projections 13 are automatically seated in the notches 18 when the knob is free.

Since the rod 7 is turnable by rotating the knob 8 and it is desired to give limited angular movement to the rod 7 to compensate for the distance 2, the slide 11 is pro* vided on its inner side with an offset or abutment 21 to limit the possible angular movemnt of the rod 7 to less than In fact, as will be seen in Figs. 3 to 5, the peg 14 abuts against one side or the other of the stop 21 when the rod 7 is driven in rotation by acting on the operating knob 8. It will be understood that by reason of the presence of the eccentric part 19 on the rod 7, any movement of rotation of the operating knob 8 will produce a slight displacement of the arm 6 either in one direction or the other direction. As a result a corresponding movement of the part 5 is produced. The margin of adjustment of said part 5 has been indicated by the distance e to an exaggerated extent in Fig. 1.

Fig. 4 shows that it is possible to indicate on the operating member 8, by an arrow 22, the mean adjusting position which is obtained when this arrow 22 is opposite the mark 23 provided on the shoe 12. Said mark 23 is particularly used in co-operation with a scale 24 marked on the shoe 12, for the usual adjustment of the length of the sewing points.

A letter A marked on the part 10 corresponds with the notch 18 which, because it is on the underside of the segment, is not readily visible from the front thereof.

Numerous modifications in construction may be provided in connection with the control device. In particular, the eccentric part 19, instead of being provided on the rod 7, may be formed by a part of the operating member 8. In this case fine adjustment is produced by a movement of the operating member 8 relatively to the shoe 12 with which it is partly engaged. It will be understood that in this case the shoe 12 should be made solid with the part 11 independently of the rod 7 so that its position is fixed by the locking members 13.

The control device described with reference to the accompanying drawing is adapted more particularly to a sewing machine. However, it will be understood that control devices of the same type may be applied to other machines, used in various industries.

We claim:

1. A control device for effecting a relatively minute adjustment of a part of a machine, said device comprising, a spindle, a stop arm radial to said spindle for engaging said part of the machine, a socket arm also radial to said spindle and angularly spaced relative to said stop arm, a rod mounted at one end in the socket arm for turning and sliding movement, an operating knob at the other end, a segment on the machine provided with at least one locking notch and a slot within and along which the length of which said rod and knob are capable of being moved, a portion of said rod being eccentric to the axis thereof, a slide mounted in said slot and having a circular bore located about the eccentric portion of said rod, diametrically opposed locking members carried by the slide and adapted for cooperation with said locking notch on the inner face of the segment, an abutment offset from the inner face of the slide, a peg passing transversely through the rod and serving as an abutment for maintaining the slide within the slot, the ends of said peg cooperating with an abutment on the slide when the rod is turned by the knob to limit the angular movement of said rod to less than 180, and the turning of said eccentric portion of said rod in the circular bore of the slide effecting relatively minute angular movement of the socket arm for a pre-selected position of the socket arm relative to said scale segment.

2. A control device for effecting a fine adjustment of a portion of a machine, comprising, a spindle, a hub pivotally mounted on said spindle, a pair of arms disposed radially to said hub, one of said arms serving as a stop for a part of the machine to be controlled and the other of said arms having a socket, a rod mounted in the socket of said last mentioned arm, a segment on the machine having a slot receiving the rod and also provided with at least one locking notch, a slide having a circular bore mounted on the rod to slide in said slot, an eccentric on the portion of the rod within said circular bore, means on the slide for engaging said notch on the segment, a shoe on the outer side of the segment, a knob on the outer end of the rod and including spring means for urging the shoe and said first mentioned means into slidable gripping engagement with the outer and inner faces of the segment, an abutment on the inner face of the slide, and diametrically opposite peg portions projecting radially of the rod, whereby, when said rod is turned by the operating knob after the shoe has been put in pre-selected position on said segment, the rod may be turned through a relatively small arc and impart small angular movement to the stop arm of the lever in engagement with the part of the machine to be minutely adjusted.

3. A control device for a machine, comprising, a pair of connected members angularly disposed and having an axis of rotation about a spindle, one of said members engageable with a part of said machine, an element carried by the other of said members and together with both members capable of being moved about said spindle to a plurality of positions, a locking device for securing said last mentioned member in a selected angular position to provide a predetermined adjustment of said machine, and said element turnably mounted in said second mentioned member and having an eccentric portion whereby turning of said element will move both of said connected members to obtain a fine adjustment of the machine.

4. A control device according to claim 3, wherein, said element is a rod extending beyond its related member and rotatably mounted therein, said rod having an eccentric portion turning in a bearing on said locking device.

References Cited in the file of this patent UNITED STATES PATENTS 676,117 Billings June 11, 1901 1,112,747 Wingo Oct. 6, 1914 1,326,166 Backus Dec. 30, 1919 1,974,197 Smith Sept. 18, 1934 2,277,966 Franzkowiak Mar. 31, 1942 2,800,806 Sangster July 30, 1957 

